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Memory Man with Double Delay Time by Kaputepalla

Posted: 02 Sep 2007, 09:29
by modman
Kaputepalla sent me these files, because he cannot post links. It's a modded EH Memory Man for double delay time.

Still looking for a corresponding schematic.

Haven't looked anything over yet, killer contribution anyways.
It's all yours to further comment on Kaputepalla...

Posted: 04 Sep 2007, 21:50
by Bernardduur
alnico wrote:i can't download the files. What are the corrections?
The audio part:
- next to the input there is a 22 uF cap; this is in fact a 2.2 uF cap
- next to the chorus / vibrato / tremolo switch there is a 12k to ground; this is corrected to a 12k AND a 2.2 uF cap in series to ground with the cap connected to ground.

The other part:
- the 1k2 resistor most left (next to trimpot) is corrected to 8k2
- the speed range caps are 0.33, 0.68 and 2,2 uF and are tantalum
- next to the intensitypot the bias divider is 9V through 330k through 330k to ground
- Cap right before bias potmeter is not 1 nF but 0,1 uF
- most right there is a connection between two opamps (one with 39k in feedback loop, one connected to the 3904); there should be a 39k resistor in that connection
- The 33R resistor is corrected to 68R

Posted: 04 Sep 2007, 23:36
by alessandro
I've made pcb and layout from the original too,but it's a double faces pcb!My pcb is more simple exept for the offboard wiring of pots and rotary selectors!Nice to meet you analog guru!!!

Posted: 05 Sep 2007, 07:54
by Bernardduur
As a mod I would love to see the stereo outputs used for some real stereo use

Posted: 13 Sep 2007, 08:22
by alsercol
Great mod!

I'll try to apply this mod in a DIY BOSS DM-2

Posted: 16 Sep 2007, 10:06
by tuemmueh
danke ;)

Posted: 18 Sep 2007, 10:44
by tuemmueh
Hi there.

I just noticed that there are a few empty solder-pads in the layout, is that correct?

cheers ... Timm

Posted: 30 Nov 2007, 11:23
by super velcroboy
thanks ;)

Posted: 14 Feb 2008, 11:15
by FXFXFX
Hey, schematic for DMM is this:

http://www.freeinfosociety.com/electron ... php?id=381

But it's not the Stereo Memory Man i think. Does the mod work on the Deluxe too?

I build some tone mods for the feedback path like this:

http://germaniumsky.com/gsky/ideas2.html

Works fine!

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 19 Apr 2008, 02:55
by omarvolta
Need a little help with this which I put together a couple of month ago. Don't have an osciloscope to calibrate it as it should but I managed to get a good sounding delay out of it. The only problem I have is that there's a high frecuency pitch sound present when the delay pot is at about 1 o'clock and the frecuency of the pitch lowers as the delays get longer. Any ideas as to what this could be?? no matter how much I mess with the trimmers I can't get rid of it. Thanks, peace.

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 19 Nov 2008, 05:25
by sfx
Hopefully this isn't a dumb question, but the daughter boards used to double the amount of delay chips looks nifty. Would this same addon board work to double the delay time on a Poly Chorus which also has a MN3005?

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 20 Nov 2008, 17:23
by sfx
Errr... nevermind I'm an idiot. The RI Polychorus uses MN3008 and 3009 chips, not the 3005.

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 24 Dec 2008, 00:07
by Rocket Roll
Probably won't manage to finish my DMM in near future (lack of MN3005 chips), but here's a small update:

- rescaled and properly oriented PCB (raster "tuned", PCB view turned into copperside view)

- added the schematics that suits this particular model for which the PCB is for (ie. the one that uses an outboard 24V power supply - all of the other schematics I've seen so far refer to older revisions, with the built-in trafo and who knows what other changes)

Haven't really checked the differences in Kaputepalla's layout against this schematics - would be nice if someone with greater skill does that! - but, from what I've seen, this is the schematics of a model from which Kaputepalla worked from. Therefore I don't know if Bernarduur's corrections (from the first page of this thread) really apply... There are some differences in power section and that's all I've noticed, but, as I've said, it would be nice if someone could checked them.

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 24 Dec 2008, 21:01
by Rocket Roll
I've forgot to add a couple of very useful files I've found here: https://www.diystompboxes.com/smfforum/ ... #msg587781

- Parts list for Kaputepalla's project (unverified by me but looking good)
- Offboard connections guide (that should follow the schematics attached in previous post)
- "EHX DMM Alignment Procedure", which seems to be factory original (but pretty old).

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 26 Dec 2008, 10:17
by Dirk_Hendrik
Rocket Roll wrote:I've forgot to add a couple of very useful files I've found here: https://www.diystompboxes.com/smfforum/ ... #msg587781
You just became my x-mas hero for '08 with this post.

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 26 Dec 2008, 10:50
by Rocket Roll
I hope you're serious - did I do something wrong again? :(

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 26 Dec 2008, 14:17
by Dirk_Hendrik
Rocket Roll wrote:I hope you're serious - did I do something wrong again? :(
Nothing. I am very serious! Really, thanks for that calibration description!

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 26 Dec 2008, 18:06
by jazzmaster
superb, my memory man still on workbench and wanted to ask here if someone has a manual for trimmer setup!

thanks a lot!

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 26 Dec 2008, 18:27
by Rocket Roll
Glad to be of help... So, if I may ask, will anybody have the time to check the schematic against Kaputepallas project?

Re: Memory Man with Double Delay Time by Kaputepalla

Posted: 01 Jan 2009, 16:33
by Rocket Roll
A couple updates:

- revised K's component layout so that one could see traces (and connections) clearly.
- offboard wiring added according to wiring layout added earlier (unverified)
- trimmers, opamps, CMOS, compander and BBDs marked according to the schematics added earlier
- attempt made to "reconstruct" LED overload section (unverified)
- attempt made to discover potential errors in K's layout (components marked with red).

Haven't really touched the power section, as it looks somewhat different on the schematics.